The present invention is related to an apparatus and method for tracing the track center of a magnetic disc with high reliability and low cost.
In the prior art, as shown in FIG. 1, the apparatus comprises a head (3) drived by a position control motor (1) which reads out inside/outside position information recorded in a position information region (Pd) of a disc (4) driven by spindle motor (2). The head 3 is connected to a preamplifier (5). The preamplifier (5) is connected to an A/D (analog to digital) converter through a peak detector (6) and sample and hold circuit (7). The A/D converter (8) is connected to a microprocessor (9). The microprocessor (9) receives index signal (SI) from the spindle motor (2) and is connected to a data latch circuit (11). The data latch circuit (11) is connected to a D/A (digital to analog) converter (10) and a position drive circuit (13). The D/A converter (10) is connected to the position drive circuit (13) through an adder (12). The position drive circuit (13) is connected to the position control motor (1).